For regular contributors to UG, ratings abuse can be very hurtful - emotionally, whatever, but in terms of site rating and points etc. It's also much more permanent to pick up enemies on UG than a site that doesn't have contributor ranking.
As such, I think blocking should remove a user's ability to vote on contributions by the person who blocked them. This way, dishonest down-votes can be avoided and users being harassed by ratings abusers need not worry about being knocked down.

I thought it did already? That people you block can't vote on your tabs/etc?
If it isn't like that, definitely agree that it should be.

Also agree that votes by friends probably shouldn't be allowed. I had one in my friend list one day just 5 star several of my tabs within a short time period. Although I think they're fine, it didn't feel right and thought it was a hint at doing the same the other way around - which is a kind of thing I expect happens a lot on here.